Fighting between Assad and rebels spills over into Israel; Syrian rights group says Islamist fighters take control of Quneitra border crossing.

Video: Tazpit

An IDF officer was lightly-to-moderately wounded Wednesday by apparent errant gun fire emanating from the Syrian side of the Golan Heights, where rebels and forces loyal to the Damascus regime are embroiled in a civil war.

The IDF responded to the cross-border fire with artillery fire of its own directed at a Syrian army post. The military stated that "a direct hit on the target was identified. We see the Syrian Army as responsible for all fire into Israel." There were no immediate reports of injuries on the Syrian side.

Between 150 to 200 rebels engaged around 100 Assad regime soldiers in Quneitra. The rebels, who include Jabhat Al-Nusra and several other organizations, took the Quneitra Crossing, but fighting continues in the town of Quneitra.

Security sources who are observing the situation said it is likely that fighting will continue, and that the Syrian army may now call for reinforcements.

The sources said the IDF is not a party to the fighting, describing the war as "an internal Syrian conflict," and that the IDF's only involvement is based on providing humanitarian aid to injured Syrian civilians, as Israel has done for the past two years.

The wounded Israeli officer was airlifted to Rambam Medical Center in Haifa for medical treatment.

Earlier Wednesday, the IDF instructed farmers and civilians to stay away from the border with Syria in the Golan Heights after intense fighting flared between the Syrian army and rebels in the Quneitra crossing region.

Explosions from the fighting in Syria were audible in the Israeli Golan Heights. The IDF said three errant mortar shells from the fighting fell in Israeli territory, damaging a pair of vehicles.

A group monitoring the Syrian conflict said on Wednesday that al-Qaida's Syria wing Nusra Front and other Islamist fighters have taken control of the Quneitra crossing, on the line dividing Syria from the Israeli Golan Heights.

The fighters, who have vowed to "liberate" the area, captured the Quneitra post on the Syrian side from forces loyal to President Bashar Assad after fierce clashes, the Syrian Observatory for Human Rights said.

The United Nations monitors the crossing that oversees traffic between the two enemy countries but the distance between the two warring adversaries' posts is some 200 meters (yards).

Fighting between Assad and rebels trying to seize the crossing has often spilled over into Israeli territory during the three-and-half year civil war.

Israel has returned fire into Syria on several occasions in the past after errant mortar shells hit Israeli territory.